One week after the National Science
Foundation chose the former Homestake gold mine in Lead, S.D., as its top proposed
site for the National Underground Science Lab (NUSL), mine owner Barrick Corporation
turned off the pumps in the deepest parts of the mine. Now, the 8,500-foot-deep
mine will slowly fill with water.

Congress
had provided Barrick $10 million to maintain the mine and keep the pumps running.
But, according to an Associated Press interview with South Dakota Gov. Mike Rounds,
Barrick did not want to be accused of taking corporate welfare. Vince
Borg, vice president of public affairs at Barrick, says that the shutdown was
always a part of the plan to properly decommission the mine. Its been
flooded before and can become dewatered again, if the NUSL plan becomes
a reality at Homestake, Borg says.

Barrick Corporation shut down the pumps
at the Homestake mine in Lead, S.D., on June 10, compromising plans for a future
underground lab. Photo courtesy of Barrick Gold.

Brian McPherson, hydrologist at the New Mexico Institute of Mining and Technology,
says that the move to shut down the pumps is a real disappointment to the scientific
community. Baseline hydrologic and thermal conditions that developed
and stabilized during the past century were destroyed when the pumps were shut
down. So, the bottom line is we really do not know what is happening at depth,
both hydrologically and thermally, and it will not be cheap or easy to determine
what is the state of flux, he says.

The flooding at depth will particularly damage geomicrobiological research opportunities,
McPherson adds. This may mean a much tougher road lies ahead for Homestake
becoming the new NUSL. The NSF site panel report, released May 28, had ranked
the Homestake mine as a more favorable site for conducting science and engineering
than the two other lead sites: a San Jacinto Mountain site near Palm Springs,
Calif., and the Soudan Mine near Tower, Minn. These sites are now under much greater
consideration than they were prior to the June 10 pump shutdown.